Rotary vane type pump



April 18, 1961 L. J. MoULToN ET AL 2,980,029

ROTARY VANE TYPE PUMP 3 Sheets-Sheet 1 Filed 00's. 5, 1956 INVENTORS NRnw/3 L fw N. T7 .0 M0, @W JJM/WH R 4. u, a .J Z

April 18, 1961 L. J. Mo'JLToN ET AL 2,980,029

ROTARY vANE TYPE PUMP Filed Oct. 5, 1956 3 Sheets-Sheet 2 4 rra HUE VApril 18, 1961' L, J, MOULTON Ef AL 2,980,029

ROTARY VANE TYPE PUMP 3 Sheets-Sheet 5 Filed Oct. 5, 1956 f//Msx [IL m oINVENTORS J. MouLTo/v BY A. L DSA/@LEE ROTARY VANE TYPE PUMP Fried oct.s, 1956, ser. No. 614,180 f 4 claim. (c1.103 1s6) The invention relatesto a rotaryA vane type pump adapted to handle liquids having corrosiveproperties and/or which may contain foreign material in forms tending tobe either destructive to certain of the pump components or to beotherwise detrimental to eflicient pumping. An object of the inventionis to providea heavy duty rotary vane type pump suitable, for example,in oil fields e.g. for gathering crude oil of various types land capableof operation without substantial slippage losses.

A further object is to provide atruly balanced and relatively highlyefficient rotary vane type pump adapted for operation to pump lowviscosity and highly volatile liquids and having effectual andpracticable provision for minimizing pressure drop in the liquid supplyand'distribution passages leading to t-he pumping chambers.

Another object is to provide a pumping chamber or barrel member for avane type pump having improved features contributing to efficientpumping and which is capable of being economically manufactured andeconomically serviced inthe field.

`Other objects of the inventioninclude provision of a rotary vane typepump so constructed that the radial movements of the vanes, apart fromtheir normal action as vanes, will act eiciently as pistons; a balancedrotary vane type pump which is capable of satisfactorily handling rawcrude petroleum notwithstanding -practically States Patent unavoidablesand and silt content thereof land which pump has effectual provisionfor minimizing unbalance in operation in event oneor more of the vanesbecomes damaged; a rotary vvane type pump having provision forcompletely isolating the necessary-rotor supporting shaft bearings fromcontact with the fluid being pumped; and

a rotary vane type pump wherein inspection and replace- Y' ment of thevan elements and other components of the pump which are apt to 'sufferwear or damage are simple operations capable of being performedexpeditiously in the field through the use of 'a' very few and commonlyavailable tools.

Other objectsand features of the invention will become apparent from thefollowing description of one preferred form of the present pump `asshown in the accompanying drawings.

In the drawings Fig. l is a small scale sectional plan view of the mainhousing po-rtion of the present pump, the housing being broken awaysubstantially along the line 1 1 of Figt 2. Fig. 2 is a sectionalv sideelevation of the pump assembly broken away as indicated bythe lines 2 2on Figs. l and 3. Fig, 3 is a central vertical secl tional view throughthe pump assembly taken along the plane indicated by the lines 3 3 onFig. 2. Fig. 3a is .an enlarged scale fragmentary view of portions ofthe construction according to Fig. 3, somewhat modified.

Fig. 4 is a detail cross sectional view showing the transverse shape ofone inlet and one outlet passage in the housing near its base portion,taken as indicated by the line 4 4 on Fig. 2. Fig. 5 is a relativelyenlarged fragmentary partlyr diagrammatic end view of thepurnpM PatentedApr. 18, 1961 ICC . 2 sleeve or barrel (hereinafter usually sleeve).Fig. 6 is a top plan reduced scale view of the sleeve. Fig. 7 is arelatively enlarged partly sectional detail side view show ing one ofthe pumping vane assemblies or vane units. Fig. 8 is a further enlargedtransverse cross sectional view through the vane unit of Fig. 7, takenalong the line 8 8 thereon, Fig. 7 showing one of several loadingsprings of the vane in a relaxed condition. fFig. 9 is a viewcorresponding to Fig. 7, partly in section and showing ya modied vaneunit construction.

The housing construction or housing means of the present pump mechanismA as shown in Figs. l, 2 and 3, preferably comprises a main body orhousing member 1, preferably made as a one-piece hollow metal castingwith an integral mounting base portion 2. and a central basicallycircular drum portion 3, and two rugged and preferably both detachableend closure members 4 and 5, shown as end caps, of mutually similar formoperatingly integral with the housing member 1, being shown as securedVthereto by screws 4' and 5 in positions closing the ends of a generallycylindrical through bore 8 in the drum portion 3 of housing member r1.The housing. con-y struction supports arotar assembly6 (hereinafterusually rotor), via its drive shaft 7.. The rotor is located coaxiallyof said generally cylindrical through bore 8 of housing member 1. Thehousing construction further includes a non-rotatably locked pump sleeve10, containing land defining portions of pump pressure chambers, to bedescribed. The sleeve 10 snugly but readily axially movably occupiesthehousing bore 8.' The sleeve 10 surrounds a generally cylindrical rotorblock 12 (fast on the shaft 7 or operatingly integral therewith), and isapproximatelycoextensive with the generally cylindrical exterior surfaceof the rotor block 12.

`The sleeve 10 forms an inner liner for the drum portion 3 of housingmember 1 and is in operative effect a rigid means to provide the housingdrum portion 3 with a generally elliptical cavity (identified bycharacters C and'C Fig. 2, describedl later), coaxial with the rotorassembly 6. The inner peripheral surface portions of thecavity,described later, define (in cooperation with the cylindrical exteriorsurface portions of the -rotor block 12 and circular annular flangeportions 14 and 15 thereof operatingly integral therewith andconstituted, as shown,

-by annular seal plates mounted on its opposite ends, see

normal to the vertical diametral axis ofthe cavity andv bisects kbothC-shaped chambers between their apical end portions as apparent frominspection of Fig. 2. The chambers C and C', Fig. 3, are substantiallyclosed axially of the pump sleeve 10 or at'its opposite ends by theilanges or circular seal plates 14 `and 15 which are detachably securedtightly, as by screws 14' and 1S', to respective end surfacesV of therotor block 12. The seal plates 14 and 15 'are centered on the block 12by respective axial rib or flange por-tions 12a of the block snuglyfitting axial circular bore surfaces 14e of respective seal plates.

` The seal plates or flanges 14 and 15, as supported and spaced apart bymain end faces of the rotor block 12, are disposed with their mutuallyfacing planar marginal surface portions in axially overlapping andfairly close clearance relationship to respective smooth end surfaces ofthe pump sleeve 10. The axialpositions of the yseal plates is fixed bythe mountings for lthe vrotor shaft 7,

described later. Radially outward circular peripheral and imperforatesurface portions of the flanges or seal plates (on sub-flange portions14a and 15a respectively) are disposed in fairly close clearancerelationship to the bore 8 in the housing drum portion 3. lTheclearancesjust mentioned result in a relatively `long and tortuous leak path (partradial and part axial) for fluid between surfaces which rotate relativeto each other and which are usually exposed to high pressuredifferential during the pumping operation. The clearance spaces aregreatly exaggerated in Fig. 3, being actually assmall as practicablewith assurance that the relatively rotating parts will normally be outof contact with eachwother during operation of the pump. p

The rotor block 12, Figs. 2 and 3, has generally radially extending anduniformly angularly spaced vane slots or ways 16 (eight being shown inFig. 2) intersecting the end surfaces and peripheral surface portions ofthe block 12; and vane assembly units 18 including-radially movable vanemembers or vanes 19 (to be more Afully described later herein) slidablyoccupy the slots or ways 16. The vanes 19 are approximately coextensiveaxially with the slot-intersected portion of the block 1,2. Suitablyrounded sealing surface portions 19 of the vanes 19 (also coextensivewith theslots axiallyof the rotor) are maintained in radially outwardlyforced sealing contact with the interior peripheral wall surfaces of thepump sleeve 10 partly by centrifugal force augmented by provision ofsprings 18a operatingly supportedby the bottom walls of slots 16 as Willbe further described later.

The vane members 19, as -Will be apparent from Figs. 2 and 3, cooperatewith the C-shaped-deningiuteiior surface portions of the sleeve 10 andwith sets or pairsof inlet ports 20 and 20 and outlet ports-22 and 22extending through respective portions of the wall of the sleeve andsubstantially in common planes transversely of the rotor axis. The portsjust above mentioned (cf. LFigs. 2 and 6) are preferably formed bydrilling groups-of holes 20h, 22h, etc. through the wall of the sleeveover areas nearly axially coextensive with the sleeve. The variousdrilled holes, as shown or indicated in the views just above mentionedextend parallel to each other or in directions non-radially of thesleeve 10` andl generally in tangential relationship to inner peripheralwall surfaces of the sleeve thus establishing ow-direction-determiningaxes for the respective ports 20, 20' etc. which are lparallel to thecenter lines of the various holes.

A distinct manufacturing advantage in drilling the sleeve-port-formingholes as just above described is that the two groups of holes (e.g. 20hand 20'h Fig-.6.) on each half of the sleeve (one such half` shown inFig. 6i) can be drilled with the sleeve 10 mounted ina single positionin a suitable tool fixture. The functional` advantages of the portdirections in sleeve 10 will be brought out later in connection with theoperating relationship of the pump sleeve to other portions ofthe pumpdescribed below. s

The ports 20, 20 and 22, 22 communicate (a) with respective fl-l anddischarge passagesA formed as cavities in the d-rum portion 3 of thehousing (as described later) and (b) with the C-shaped cavities C and C'to form or establish a pair of inlet or charging pump chambers F and Fdisposed diametrically of the rotor block 12 and a pair of outlet ordischarge pump chambers P and P' also disposed diametrically of theblock 12. The pair of ll or charging chambers F and F and the pair ofdischarge chambers P and P', which vary in volumeaccording to vaneposition, are angularly related Ato diametrically located seal regionsor yareas S and S between the rotor block 12 and the sleeve 10 (areasbisected by the plane indicated by line 3-3 on Fig. 2 which-line therebyidentifies the diametral axis of the sealing surface regions) so thatthe hydrostatic pressure forces incident to pumping are balanceddiametrically of the rotor axis, as Well known in the relevfantarduringthe pumping operation.

The diametrically opposite seal areas S and S lie bebetween closelyspaced external cylindrical surface portions 12b of rotor block 12 and`adjacent internal surface portions of the pump sleeve 10, and theclearances are on the order of those establishing the leak pathsadjacent the seal plates 14 and 15 as described above. The seal areas Sand S are of substantial angular or circumferential extent about therotor axis, being Aapproximately 20, as Shown. That is something overtwice the circircumferential width of the vane slots 16. Internalperipheral surface portions T and T of the sleeve 10, located betweenthe pumping chambers F and P and F and P respectively, are concentricwith the rotor assembly axis. The surface portions T and T of thesleeve, in cooperation with other above described defining walls of theC-Shaped chambers C and C', including relatively adjacent vane members19, constitute transport channels of uniform transverse area, as wellunderstood in the vane type pump art. The vane position controllinginternal surfaces of the sleeve, all similarly indicated at R, in Fig.2, and which constitute apical wall portions of the C-shaped chambers `C`and C will be further described later in reference to Fig. 5.

Uniformity of ilow resistance and pressure drop Iis critically importantin the inlet or pump-chamber-feeder passages of the pump, especiallywhen volatile liquids (those especially subject to cavitation) are to behandled thereby. Uniformty of flow resistance in the various outlet ordischarge passages is, of course, also desirable but is much lessimportant.

Provision of a heavy duty rotary vane type pump arranged for balancedoperation as identified above and with main feeder and discharge conduitconnections lo- `cated coaxially atsuitable height and atright angles tothe rotor axis (as most desirable for field installation and service)can be most electually designed with branch kpassages in the pump bodyextending from the main inlet and outlet passages around the pump bodyto cooperating rotor-associated and circumferentially aligned inlet andoutlet' ports located diiferent distances from the regions ofintroduction and discharge of liquid into Iand out of ,left Fig. 2) with`a 4relatively short branch passage leading to near inlet port 20 and alonger passage leading to far inlet port 20 of pump sleeve 10.

Referring more specifically to the main pump housing section or body 1(especially `as shown in Figs. l, 2, 3 and 4), the formation of liquidsupply passages or channels in said body section through and from maininlet channel 30 of `flange formation 25 to the sleeve inlet ports 20and 20 and from the sleeve outlet ports 22 and 22 to and through mainoutlet channel 36 of flange formation 26 is such that the ow Iresistanceor pressure drop inthe passage portions communicating with therelatively near and far ports isapproximately uniform. That result isattained inter alia, in the arrangement as illustrated, by locating themain inlet and outlet passages or channels 30 and 36 with theirpreferably common axis in olset relation to the horizontal plane of therotor axis on the side of that plane (advantageously below or aS shown)on which branch passage .portions 33 and 34 of said channels 30 and 36respectively are extended around the pump sleeve 10 past the rotor axisand in crosswise relationship to each other (see especially Fig. 1) inorder vto communicate at their fluid discharged terminal portions(adjacent the sleeve 10) with associated circumferentially alignedrelatively far ports 20' and 22 respectively'through the wall of thepump sleeve 10. Thus the upper branch passages 32 and 35 (Fig. 2) whichextend to or from the relatively near `and circumferentially alignedports 20 and 22 of the sleeve 10 in respect to associated main channels(30 and 36) are not materially shorter than the corresponding lowerbranch passages v33 and 34 leading to the far ports.

'Additionally,Y for minimizing undesired difference in pressure drop asdiscussed above, the relatively longer pump chamber feeder and dischargepassages leading to their discharge or intake terminalportions'adjacentthe cooperating ports are the less tortuous. This isattained in large part by the already described direction of extent ofthe effective axes of the inlet and outlet ports in the pump sleeverelative to the pumping chambers and relative to the branch passagesleading to and away from the ports of the sleeve in the directions ofpassage of liquid in and through the pump. As made apparent in Fig. 2fluid entering the cavity C through the upper branch inlet passage 32makes a relatively sharp turn in order to get through the sleevedrillings h constituting inlet port 20, whereas the discharge end of thelower inlet branch passage 33 is effectively aligned with the drillings2071 forming inlet port 20. The outlet branch passages or channels aresimilarly related to the associated outlet ports of sleeve 1t) as willbe apparent.

In addition to the horizontally offset location of main inlet and outletpassages or channels relative to the rotor axis and other features ofthe'passages described above, and especially in order to encourageeasy-filling flow to the inlet portions F and F of the C-shaped chambersC and C the inlet or feed passages, both in the main casting l and inthe sleeve 10, are, generally atleast, formed with larger effectivetransverse areas than those of corresponding portions of the outletpassages. As shown in Figs. 2 and 6, the tangentially extendinginletport-forming holes (e.g. 20h) in the pump sleeve 10 are nearlytwice as numerous as the-discharge-port-forming holes (e.g. 22h) in thesleeve, all the holes however vpreferably being of uniform diameter forproduction economy.

In order to encourage the ultimate user of the pump to providesubstantial fill capacity conduits in installing the present pump theinlet flange 25 is designed to be coupled to a suitable standard sizerelatively large diameter feeder conduit (e.g. 3" inner diameter), andthe outlet flange 26 is adapted to be coupled to a relatively smalldiameter but standard discharge conduit (e.g. 2" inner diameter). i

Referring further to the liquid flow passages or channels formed ascavities in body casting 1, liquid entering the inlet passage 30, leftFig. 2, is divided or deflected toward respective branch passageportions 32 and 33 by a suitably shaped rib 30a extending entirelyacross the main passage 30 and whose surfaces define radially inwardwall portions of the branch passages 32 and 33. A similar liquid guiderib 36a extending across the outlet passage or channel 36 assists inmerging the outlet branch passages 34 and 3S smoothly therewith. Theupper inlet and outlet branch passages 32 and 35 are of generallyrectangular elongated form in cross section (not fully illustrated). Allthe branch passage portions which are formed in the drum portion 3 ofthe casting 1 are extended laterally, mainly for the sake' of uniformityof Y casting wall thickness, as by transversely aligned horizontallyextending cavities (typical disposition indicatedn at 32e and 35e Fig.2) in available locations not intersected by holes for theend-cap-attaching screws 4' and 5.

As seen by comparison of Figs. l, 2, 3 and 4, the lower inlet branchpassage 33, below the deflector 30a, turns downwardly and toward theright vfrom the point of view of a coupler attached to inlet flange 25and, at the transverse plane of Fig. 3 or directly below the rotorassembly, the passage y33 has the horizontally elongated more or lessrectangular form as indicated at 33b in Fig. 3. Lower outlet branchpassage 34 turns rightward (same point of view) from the cavity 34awhich intersects main casting bore 8 for communication with the pumpsleeve discharge port 22, and, below the rotor asy so-that, in theregion of section-indicating line 4-4 on passage 33 intersects thethrough bore 8 in casting 1 in registration with the vertically disposedfiller port drillings 20h. The lower outlet branch passage 34 underliesthe inlet branch cavity portion 33a,.as shown in Fig. 4, meanwhileturning toward the right in order to merge withl the main outlet passage36 centrally of the casting 1 in reference to the drum portion 3 and theinlet and outlet flanges 25 and 26. v l

Fig. 4, incidentally, shows substantially the manner in which one of theinlet passage-branch portions (33 only in Fig. 4) is extended laterallyat at 33e in appropriate places as already mentioned. The extensions arecommunicated with Yspaces V and V', Fig. 3, adjacent the end portions ofthe rotor block 12 through` radial passages such as 33d and 33e, Fig. 4.Thereby the faces of the rotor block 12, Fig. 3, and the attached sealplates 14 and 15 which are exposed axially of the rotor block in saidspaces V and V (equal total areas exposed in each) are subjected tobalanced and relatively low hydrostatic pressure forces. Further theseal assemblies 44 and 45, Fig. 3, are similarly subjected to relativelylow and hydrostatically balanced pressures axially of the assemblieswhich, particularly, cannot expose the carhon portions 44a and 45a ofthe seals to destructive forces. n

Outboard bearing assembly 40, left Fig. 3 (fully secured in end cap 5against axial movement and secured to the rotor shaft against axialmovement relatively thereto as will be described) fixes the axialposition of the rotor head 12 which preferably is shrink fitted to vtheassociated largest diameter portion 7a of the shaft 7. Thus as pumpoutput axially balanced high pressures occur in the planar clearancespaces between the two seal plates 14 and 15 and the associated ends ofpump sleeve 10 (portions of the leak paths described above) Vthe pumpsleeve is hydrostatically centered between the two seal plates and noaxial forces of any consequence are imposed on the bearing assemblywhich determines the axial position of the rotor.

The four vane-position-control (cam or guide) portions or regions R ofthe pump sleeve 10, as best shown in Fig. 5, preferably have identicalcontours. Each region R, as shown, extends for approximately 30"circumferentially of the sleeve 10 about its center or axis O which isalso the axis of the rotor. Each vane position control region comprisesa planar surface 10b tangent to the adjacent sealing internal surface10a of the sleeve and which defines, with the yperiphery of the rotorhead 12, the seal region S or S of substantial circumferential extent(angle Sx) as earlier described in reference to Fig. 2. The vanes 19while traversing the planar guide surface 10b are not subjected tocentrifugal force but, in the absence of vane loading spring force,would nevertheless stay in sealing contact with surface 10bV because ofthe inherent tendency for any body to move in a straight line. Foroperatingly merging the plane surface 10b smoothly into thetransport-area-defining concentric internal surface T of the sleeve asuitable arcuate surface 10c is formed on a radius Y whose length isconsiderably less than the radius of seal surface 10a (radius Y beingshown as about half the radius of portion T) the surface 10c beingtangent to planar surface 10b and to the arc ywhich defines associatedsurface T. Thereby the lvanes 19 move from their maximum inwardpositions (seal regions S or S) to their maximum outward positions (incontact with surface T) in about 30 of rotation (angle Rx) or relativelyvery quickly in order to minimize intake losses. The charging or intakeports (holes 20h and 20h), due largely to their tangential directionalready described, extend through approximately v(angle Tx plus Rx) onthe inside of the sleeve 10', so that the effective fill chambers F andF', after the vanes 4are no longer acting to enlarge the transverseareas of the ll chambers, have ample time Ato become fully charged. Thedirections of extent of the holes 20h and 20h further favors fullcharging since the charging flow direction through the intake ports intothe chambers C and C is to a large extent tangentially of said chambers.The discharge ports (22 only being shown in Fig. 5) are approximatelycoextensive circumferentially of the sleeve 1 0 with the associated vanecontrol or camming surfaces R.

The vane assembly units 18, oneV of which is shown in detail in Figs. 7and 8, in addition to the flat platelike vanes or vane members 19 ofrectangular form as shown in Fig. 7 and their springs 18a alreadymentioned in clude supporting lstrips 18b for the springs occupying thebottoms of respective vane slots 1.6. The springs 18a are preferablyhelical wirecoils spaced approximately equal distances apart along eachvane mainly by respective parallel sockets 50 intersecting the radiallyinwardly exposed generally flat edge face 51 of the vane, which facelies adjacent the bottom of an associated vane s lot 16 as shown in Fig.2. The supporting strip 18b has shallow circularsockets 52 for receivingand further positioning associated end coils of respective springs 18aas best shown in Fig. 8.

In order that the spring coils intermediately of the ends of the springs18a will not be in rubbing contact with the Walls of the sockets 50 inthe vanes, the end coils, as 18C and 18d, Fig. 8, of the various springs18a are of larger diameters than those of the interme- `diate coils.This Vsame coil diameter relationship enables the springs (through tightengagement of their end coils with associated Side wall portions of thesockets 50 of the vanes and the sockets 52 of the positioning strips18b) to retain together the components comprising each vane assembly 18for package or unitary insertion into the rotor slots 16 and removaltherefrom,

Part or all of the sockets 52 in each spring supporting strip 18b haveholes 53 in their bottom Walls intersecting the under face of the stripfor uid passage through `the strip as will be explained presently. Forlluid communication between the spaces lying radially under the vanes orin the bottoms of the vane slots and whatever ll or discharge chamber(F, F', P or P) the vanes happen to be exposed in, holes 54 in theradially outward portions of the vanes 19 (eccentric to the sockets 50as shown in fFig. 8) intersect the sockets 50 or some .of them. Thesealing rib portions 19 of the vanes 19 trail the associated holes 54 ofthe vanes in respect to the direction the rotor turns (counterclockwiseas indicated in Fig. 2). Thereby, las earlier mentioned, the vanes actas pumping pistons contributing materially to the capacity of the pump,and hydrostatic pressures due to pumping are approximately equalized onthe radially outward and radially inward faces or edges of the vanes.

In. order to minimize unbalanced hydrostatic forces diametrically of therotor assemblyI 6 in event of damage to the Vane seal rib portions 19(e.g. abrasion or chipping of the ribs as by sand or hard particles inthe fluid being pumped)the vane slots 16 are cross connected in pairsdiametrally of the rotor head by angularly related passages 56, 57, 58and 59 (see Fig. 2). These passages can be economically formed in therotor block 12 and shaft portion 7a after the block is mount- .ed on theshaft. The passages 56, 57, 58 `and 59 are communicated at opposite endssuccessively with the pressure spaces P and P through the openings 54 inthe vanes 19 and the openings 53 in the vane spring positioning strips1811 already described above.

While the material for the vanes 19 is selected according to use ahighly satisfactory vane composition for pumping crude oil for exampleis inherently strong and tough, acid andhydrocarbon resistant,thermosetting synthetic resin. Such can be moulded and/or machined tothe` required shapes or as shown by comparison of Figs. 7. and.8. Thesprings 18a are preferably made of corrosionI resistant metal forexample beryllium copper alloy or stainless steel. The rotor block 12and sleeve 10 are'preferably tough hard steel. The seal plates 14 and 15may be bronze but, for greater strength they would also be suitablesteel sheathed with a bearing material Suited lfor operation inassociation with the ferrous metals used for the sleeve 10 and housing1.

Referring further to Fig. 3 which best illustrates the preferredmounting for the rotor shaft 7, adequate provision is made forinspection of the pump chambers and lfor expeditious removal andreplacement of vane units 18, via removal of the end cap 5, i.e. themain housing bore closure which lies outboard with reference vto thepump driving mechanism not shown (coupling, transmission, etc.) whichtherefore need not be disturbed in order to enable routine inspectionand performance of usual service operations.

' Characteristics of end vcap 5 (left, Fig. 3) which are common to bothend caps 4 and 5 Will be described below solely in reference to end cap5; and the reference characters applicable to operationally identicalfeatures of the end capswill be mentioned only in respect to end cap 5.

End cap 5 has a stepped diameter generally cylindrical portion 60 forsnug slip-fitting relationship to the main casting bore 8, the portion60 being grooved at 61 for reception of'a resilient or other ring typeseal 62 to prevent leakage of low pressure pumped fluid out of space V.An annular closure plate 63, complemented by an easily detachable springcap 63a adjacent to the outboard end of the drive shaft 7 is disposed inaxial alignment with the bearing 'assembly 40. Closure plate 63 issecured in a circular recess or counterbore 64 of the endA cap 5 as byscrews 65. An inner face 66 of the plate 63 is forced by the attachingscrews 65 against one axial end portion lof the outer race ring member40a of bearing assembly 40. The inner race ring member 40hV of thebearing assembly is press or shrink fitted to the reduced diameter endportion 7b of shaft 7 against a leftwardly facing shoulder 7c on theshaft. A radially expansible (for release) snap ring 67 occupies aperipheral groove 68 in the outer race ring 40a of the bearing 40, sothat the position of the snap ring can determine the position of thebearing assembly 40 (hence the position of the shaft `7 and other partsof the rotor assembly -6` lixedly secured thereto) axially of thehousing 1, via the fixed position of the end cap 5 on the main housing.A fairly large clearance space 69 between the annular plate 63 and thebottom of the counterbore or recess 64 in the end cap 5 enablesassurance of right- Ward takeup pressure of plate surface 66 against theouter bearing race 40a and, therethrough, rightward pressure of theradially outward margin of the snap ring 67 against the bottom of saidcounterbore 64. Thereby, when the screws 65 of plate 63 are tightlyseated against said closure plate, the shaft 7 is elfectually preventedfrom' axial movement relative to the pump housing,

Spring cap 63a in alignment with the outboard end of shaft 7 enablesready' access to the shaft (inboard end normally inaccessible) formeasuring pump rotor speed after installation and during trial operationof the pump.

The spring loaded seal assembly 44 around the shaft 7 (left Fig. 3), ispartially contained in a generally cylindrical sleeve 70 having ringtype seals 70a and 70b similar to 62 (previously described), oneexternally around a portion 44b of the seal assembly 44 and oneinternally around the cylindrical counterbore surface 72 of end cap 5into which the sleeve 70 can slide easily. In order for the sealassembly 44 to operate properly the sleeve 70 must be prevented fromrotating with the shaft 7; and that function, in the illustratedarrangement, is accomplished by provision of a radial pin 75 carried bythe sleeve 70 and of a pin 76 projecting inwardly from the end cap 5normalto the axis of pin 75 or so as to be in the'path of attempted fullcircle rotation on part r "mit of the pin 75 with the rotor assembly.-The central openmg, 14e. of the seal plate 14 which ts over theassociated rib 12a of the rotor block 12 is larger in diameter than theseal retainer sleeve 70, and alradial slot 141, Fig. 2, intersectingsaid central opening 14e permits the seal plate 14 to clear the radiallyextending pin 75 of sleeve 70 during removal of the seal plate `14 outof main casting bore S.

Still referring to Fig. 3, it willbe apparent thatV the end cap can beremoved from its illustrated position (leftwardly, Fig. 3), leaving thebearing assembly 40 andthe seal assembly 44 in theirillustrated-'positions on their'then cantilever-supported.associatedportions of the shaft 7. That end-cap-detachng operation exposes, interalia, the leftwardly facing surfaces of theseal plate 14 and itsattaching screws 14. The seal plate 14 can thus be detached from therotor assembly and slid out of the casting bore 8, thereby to expose the`outboard ends of the vane assemblies 18.

Extraction of the vane assemblies 18 from their slots or ways 16 of therotor block is facilitated by provision of threaded sockets 78 (see Fig.7) inthe end portions of the vanes 19 axially of the rotor assembly 6.The threads and diameters of the sockets 78 can be the same (forexample) as those of the screws 14' or 15', which secure the seal plates14 and 15 to the rotor block (or the same as those which secure the cap1c, Fig. 2, to the housing 1) whereby readily available screws can beused to extract the vane units or assemblies 18 from the vane slots 16of the rotor block. Extraction of the vane units 1.8 is accomplishedeasily when the units are in their maximum outward positions, namelywhen the units are in the chambersCorC. v f

If the pump sleeve requiresremoval from itsposition for inspection orreplacement this can be accomplished through the outboard end of maincasting bore 8 after removal of key `1b. Y

During replacement of the end cap 5 (and during its initial installationinto the housing 1) the seal ring 7Gb around the sleeve 7 (l of sealassembly 44 is apt to be so expanded radially as to resist entering itsreceivingcounterbore 72 in the end cap 5. To make certain that thesleeve 70 will be moved yinto seated position without danger of damagingthe seal assembly a cuplike metal sleeve 80 is provided around theVloading springof seal assembly 44 and the iiange portion 81 is sopositioned relativer to the sleeve 70 as to thrustl that sleeveapproximately intojits properly seated (illustrated) position while theend cap 5 is being initially installed or is being replaced followingthe above described vane inspection or replacement operations. i

The inboard shaft mounting and seal construction shown at the right inFig. 3 is basically the same as the outboard construction describedabove except thatr the outer race ring 41a of bearing assembly 41 has aslip fit in a counterbore 32 in the end cap 4 to permit installation ofthat end cap over the inboard bearing whose inner race ring 41b is xedto the drive shaft, as by press or shrink iitting. End cap 4 has aradially inwardly extending flange portion 4f shrouding the inboardbearing assembly 41.

The self contained vane assembly or unit 18 constituted by a vane member19; a spring positioning strip or plate 18b, and the associated coilsprings 18a, as earlier above described in reference to Figs. 7 and 8,does not enable the vane units 18 to be very easily inserted into thevane ways or slots 16 except when a guide iixture (such as adouble-open-ended sleeve is used to contain the components with thesprings 18a in compressed condition, not illustrated). Furthermore if,for self-containment of the components, the -spring end Vcoils (see 18eand 18d in Fig. 8) are tight in the sockets 50 and 52 of the vanes andsupporting strips the spring-coils intermediately of the ends of thesprings can be subjected to slight torque during cyclical compressionand/or expansion. The end coils of the springs may be entirely free fromtorque restraint by retaining socketwalls in the self-contained vaneunit assembly 118 described below in reference to Fig. 9. In Fig. 9 thevane `119 has ('for example, near its two ends axially of the rotor andoccupying vrespective regions which, in the Fig. 7 illustratedconstruction, are occupied by springs 18a) latch devices 120 formed, forexample by pins 121 (one shown) suitably fixed to thecoil-springsupporting strip 118b; The pin 121, as shown in Fig. 9,projects into a circular bore 122 in the bottom wall of vane 119,.whichbore is somewhat larger in diameter than the headportion y124 of the pin121. Counterbore 125 of bore 122 (shown plugged) forms a shoulder126.When the spring supporting strip 118b andthe vane 119 have theirleftward end surfaces disaligned, a small distance, as illustrated atthe left in Fig. 9, the head 124 can (with the-springs 18a compressedaxially to a greater extent than they ever are in the operation in thepump) be frictionally latched on the Counterbore shoulder 126. Thus itis an easy operation to insert the latched vane units 118 into the rotorblock slots 16 in any position of those slots. After insertion theleftward end surfaces of the vanes 119 and the supporting strips aremoved into kflush relationship to each other, releasing the latchconnec'tions described above; and obviously the-heads 124 of the pins121 cannot then lbe re-latched on the shoulders 126 during operation ofthe pump.

In Fig. 3a, the snap ring 67 is of tapered or wedge-like cross sectionalform and is seated into a generally cornplementary `groove 68 in theouter bearing race member 40a of bearing assembly 46, so that the snapring has no side clearance, axially of the rotor assembly 6i, between itand the side-defining surfaces of the groove. In this modication, whenthe annular plate member 63' is secured in end cap 5 by tightening ofattaching lscrews 65, an inner face 66' of the plate 63' clamps the snapring 67' against the bottom of counterbore 64 of end cap 5, and the snapring `67' is subjected lsubstantially only to shear stress in holdingthe rotor assembly 6 axially inl position.

In Fig. 3a it is apparent that the shielding, partially shown at 40C, ofbearing assembly 40 provides a labyrinth andi/or corrosive fluids suchas can be handled by the A fprese'nt pump. To prevent accumulation ofsuch fluids in '45 thefspaces between the rotor shaft seal assemblies 44and 45 and the bearingv assemblies 40 andr41 (in case, for example-ofymalfunctioning of the seal assemblies), suitable ydrain passages; leadfrom the respective spaces just above mentioned to points externallyofthe pump housing. Such passages 40d and 41d Fig.. 3 areindicated asformed in respective end caps'5 and 4, the outer ends of the passavesbeing adapted for connection to suitabletubing.

The inlet and outlet branch passage or channel vportions 33b and 34h inthe main housing member 1, as shown in Fig. 3, have Adrain and iiuidinspection holes 33h and 34h shown closed by suitable threaded plugs.'

Pressure gages or emergency reliefy valve mechanism (neither shown) canbe connected at the holes 33h and 34h or at other similar holes (notshown) in appropriate portions ofthe housing.

We claim: n

l. A vane type rotary pump comprising a housing having a cylindricalbore, a rigid metal sleeve lining said bore, a cylindrical rotor for thevanes arranged to operate in a cavity in the sleeve providing with therotor diametrically-opposite arcuate pumping chambers and diametricallyopposite sealing surfaces in a diametrical plane at right angles to thatof the pumping chambers, each chamber having inlet ports formed by a.plurality of cylindrical holes in the sleeve having mutually parallelaxes which are also parallel to said diametrical plane, a submetricalplane and respective long and short branches extending circumferentiallyof the sleeve radially outwardly therefrom and communicating the mainpassages with respectively associated ports, the main inlet passagehaving a longitudinal axis perpendicular to said diametrical plane andintersecting it in offset relation to the rotor axis in a directiontoward 'the long inlet branch;

2. The pump according to claim 1 wherein the sleeve is slidably butnon-rotatably tted in the cylindrical bore of the housing, end portionsof the rotor having circular anges rigid therewith and overlappingrespective ends of the sleeve and -the interior of said bore close toeach, thereby establishing in conjunction with the sleeve and housingbore radially and axially extending leak paths, together with bearingmeans supporting the rotor in axially xed position in the housing andthereby, through the agency of the flanges, determining the axialposition of the sleeve.

3. In a rotary pump, a main housing member having an approximatelycylindrical bore and closure means for respective ends of the bore, oneof said closure means being detachable from the main housing member toexpose one end of the bore, means forming a pump barrel concentricallyof the bore, a pumping rotor assembly coaxially of lthe bore and havingfluid impelling means cooperating with the barrel forming means to pumpfluid, said rotor assembly including a supporting shaft, a portion ofthe shaft having a bearing supporting it in one of said closure means, aball bearing assembly supporting another portion of 4the shaft in saidother closure means, said ball bearing assembly including an inner ballrace member fast on the associated portion of the shaft and an outerball race member slidable in a cylindrical bore portionof said otherclosure means, the balls of said bearing assembly preventing substantialaxial relative movement of the race members axially of the rotorassembly, the outer race member having a retainer ring removably securedthereto marginally 'adjacent a rigid wall surface portion of said otherclosure means facing axially of the rotor assembly toward said otherclosure means, a substantially rigid plate member and means detachablyclamping that member to said other closure means and meanwhile operatingto force the retainer ring tightly against saidrigid wall surfaceportion of that closure means, said means forming the pump barrelincluding a generally cylindrical sleeve keyed to the main housingmember and axially movable in and externally mating 'the cylindricalbore and further including seal plates rigid with opposite effective endportions of the rotor assembly marginally overlapping respective endsurface portions of the sleeve so that the position of the sleeveaxially of the bore is maintained by said ball bearing'assembly and itsassociated elements.

4. In a vane type rotary pump having a generally cylindrical radiallyslotted rotor for the vanes operating in a cavity providing an arcuatepumping chamber and sealing surface regions at circumferential ends ofthe chamber and inlet and discharge passages for fluid communicatingwith the chamber, a self contained vane assembly in a slot of Ythe rotorand comprising a vane element slidably fittingV the slot, an auxiliarymember slidably fltting the slot, the vane element and auxiliary memberbeing of approximately equal length and coextensive with the slotaxially of the rotor, and radially acting compression spring meansbetween said vane element and auxiliaryv member, a plate detachablysecured to one end of the rotor and defining one axial end of the slot,and retaining latch means comprising a` pair of headed parallel pins ontheauxiliary member loosely occupying respective sockets in the vaneelement, the sockets having shoulders positioned to abut the respectiveheads of the pins when the-auxiliary memberV and vanev element are in anabnormal relatively offset position axially of the rotor for holding thesprings in compressed conditions, the headsI releasing the shoulderswhen the element and member have been moved in that direction to anormal working mutually registering position.

References Cited in the flle of this patent UNITED STATES PATENTS1,101,688 Diamant .Tune 30, 1914 1,635,006 Oliver July 5, 1927 1,769,647Press July 1, 1930 1,776,452 Rosenthal Sept. 23, 1930 1,807,392 DavisMay 26, 1931 1,898,914 Vickers Feb. 21, 1933 2,170,786 McElroy Aug. 22,1939 2,255,785 Kendrick Sept. 16, 1941 2,400,286 Buckbee May 14, 19462,491,100 Frei ,Dec. 13, 1949 2,498,029 Clerc Feb. 21, 1950 2,498,826Ruona Feb. 28, 1950 2,525,619 Roth et al. Oct. 10, 1950 2,545,238MacMillin et al.v Mar. 13, 1951 2,558,837 Frei July 3, 1951 2,650,573Hickman Sept. 1, 1953 2,696,787 Jaworowski et al. Dec. 14, 19542,731,919 Prendergast Jan. 24, 1956 2,762,312 Adams'et al. Sept. 11,1956 2,787,959 Jeannin et'al Apr. 9, 1957 2,856,860 Roth Oct. 21, 1958FOREIGN PATENTS 21,191 Norway Feb. 20, 1911 409,958 France Mar. 4, 1910`508,748 i Germany Oct. 1, 1930 V` 583,973

France Nov. 12, 1924

